As Palestinian rockets head toward Tel Aviv — Israel’s most densely-populated area — in retaliation for Israel’s killing of the Hamas military chief, the U.S. is urging a de-escalation of the violence.

At Thursday’s State Department briefing deputy spokesperson Mark Toner echoed the White House position that the escalating tensions on the Israel/Gaza border are being driven by the actions of Hamas.

Toner pointed out that over 100 rockets have been fired from Gaza into Southern Israel on Thursday alone and the United States stands by Israel’s right to defend itself.

“The Israeli government noted that since the beginning of 2012, more than 768 rockets have been fired into Israel from Gaza, and over 12,000 in the past 12 years, and I believe over a hundred today alone,” he said. “They have a right to self-defense.”

But Toner was challenged by members of the press corps, particularly those from the region, about U.S. response to Israel’s actions as well. Reporters asked if the U.S. is counting the number of rockets and air raids that Israel has conducted on Gaza over the same period of time and also whether Palestinians in Gaza have the same right to self defense. Toner deflected answering those questions directly, but said that the United States unequivocally places the responsibility of ceasing the violence on Hamas.

“This is violence instigated by Hamas,” said Toner. “As we’ve said very clearly in our statement yesterday, that we extend our sympathies to the victims, innocent Israeli and Palestinian civilians that have been affected by this violence. But let’s be very clear where the onus lies.”

“Our position is clear that there’s no justification for the violence that Hamas and other terrorist organizations are employing against Israel,” he said. “And the onus is on them to cease their rocket attacks so that this de- escalation can take place.”